Chapter 8
Response of UHPCC-FST Subjected
to Low-Velocity Impact
8.1 Introduction
Concrete filled steel tube (CFST) has been extensively applied as the load-bearing
members in critical infrastructures, e.g., the high-rise buildings, bridges and electricity transmission towers due to their enhanced compressive and flexural performances, improved ductility and economic advantage (Zhao et al. 2010; Uy 1998).
One important load condition that must be considered in some structural design situations is the impact load which can cause severe damage to structures. For example,
bridge piers located close to a navigable waterway may be vulnerable to vessel collisions (Sha and Hao 2013), bridge piers in mountain areas may be hit by falling
rocks (Lu and Zhang 2012) and the viaduct piers may be impacted by heavy vehicles (Thilakarathna et al. 2010). Once the above CFST members are damaged, it
may lead to serious consequences of infrastructure collapse. Several design codes
offer general rules for the design of structures under impact load. Eurocode 1 (Draft
prEN 1991-1-7, 2005) provides the formulas for calculating an equivalent static force
on structures in an impact event based on the type of traffic (i.e., vehicle or ship).
However, the real impact process is ignored in the current design guidance. For more
precise design purposes, the impact performance of specific structural type should
be studied in detail. Hence, it is of great importance to evaluate the performance of
CFST subjected to transverse impact.
Most existing works (Madurapperuma and Wijeyewickrema 2013; Adhikary et al.
1997; Zhan et al. 2015; Yoo et al. 2016) are focused on the reinforced concrete
(RC) column, which showed that the RC columns may suffer localized damage
(e.g., spalling of concrete cover and diagonal shear cracks) or global damage (e.g.,
flexure). Comparably, the outer steel tube of CFST column could effectively prevent
the spall damage of concrete and reducing the localized damage of the CFST column
under transverse impact load. Bambach et al. (2008) performed a series of drop
hammer tests to study the fully clamped hollow and concrete (compressive strength
of 88.4 MPa) filled steel square beams subjected to low-velocity and large mass
© Science Press 2021
Q. Fang et al., UHPCC Under Impact and Blast,
https://doi.org/10.1007/978-981-33-6842-2_8
237
Response of UHPCC-FST Subjected
to Low-Velocity Impact
8.1 Introduction
Concrete filled steel tube (CFST) has been extensively applied as the load-bearing
members in critical infrastructures, e.g., the high-rise buildings, bridges and electricity transmission towers due to their enhanced compressive and flexural performances, improved ductility and economic advantage (Zhao et al. 2010; Uy 1998).
One important load condition that must be considered in some structural design situations is the impact load which can cause severe damage to structures. For example,
bridge piers located close to a navigable waterway may be vulnerable to vessel collisions (Sha and Hao 2013), bridge piers in mountain areas may be hit by falling
rocks (Lu and Zhang 2012) and the viaduct piers may be impacted by heavy vehicles (Thilakarathna et al. 2010). Once the above CFST members are damaged, it
may lead to serious consequences of infrastructure collapse. Several design codes
offer general rules for the design of structures under impact load. Eurocode 1 (Draft
prEN 1991-1-7, 2005) provides the formulas for calculating an equivalent static force
on structures in an impact event based on the type of traffic (i.e., vehicle or ship).
However, the real impact process is ignored in the current design guidance. For more
precise design purposes, the impact performance of specific structural type should
be studied in detail. Hence, it is of great importance to evaluate the performance of
CFST subjected to transverse impact.
Most existing works (Madurapperuma and Wijeyewickrema 2013; Adhikary et al.
1997; Zhan et al. 2015; Yoo et al. 2016) are focused on the reinforced concrete
(RC) column, which showed that the RC columns may suffer localized damage
(e.g., spalling of concrete cover and diagonal shear cracks) or global damage (e.g.,
flexure). Comparably, the outer steel tube of CFST column could effectively prevent
the spall damage of concrete and reducing the localized damage of the CFST column
under transverse impact load. Bambach et al. (2008) performed a series of drop
hammer tests to study the fully clamped hollow and concrete (compressive strength
of 88.4 MPa) filled steel square beams subjected to low-velocity and large mass
© Science Press 2021
Q. Fang et al., UHPCC Under Impact and Blast,
https://doi.org/10.1007/978-981-33-6842-2_8
237